Hydraulic cam adjuster



cfc. MOORE ETAL 459,713

HYDRAULIC CAM ADJUSTER Ja. 18, 1949.y

File d Feb. 20, 1946 2 Sheets--SheerI 1 CHESTER C. MOORE CRL E. KING JR' THE Jan. 18, 1949.

C. C. MOORE ET AL HYDRAULIC CAM ADJUs'TER Filed Feb. 20, 1946 2 Sheets-Sheet 2 Y CHESTER C. Moons Cam. E Km'e Jn.

Patented Jan. 18, 1949 UNITED STATES PATENT GFFICE HYDRAULIC CAM Anms'rnn Chester C. Moore and Carl F. King, Jr., Aurora, Ill., assignors to Stephens-Adamson Mfg. Co., Aurora, Ill., a corporation of Illinois Application February 20, 1946, Serial No. 648,934

(ci. 'r1-3) s claims.

carriage as been accomplished by spaced opposedr rigid cams acting on a carriage carried follower between the cams and riding thereon.' Results obtainable with such arrangement are not highly accurate because the follower must have operating clearance between the cams so that it will not bind. In addition, the opposed rigid cams are subject to the wearing action of the follower riding thereon. Play or looseness is thus necessarily present in the control and results become less and less accurate as the lathe is used for mass production of parts.

Another disadvantage in heretofore known conn trolled cam rocking of a lathe carriage is the requirement for double sets of cams for each profile or contour to be turned. The arrangement is therefore expensive.

According to the present invention only one cam is needed for each 4prole or contour and the cam follower on the lathe carriage is caused to ride on this single cam with a carefully controlled predetermined amount of pressure that will not vary as the follower moves between high and low spots on the cam. The predetermined pressure is produced by a fiuid pressure actuated jack subjected to the action of cil or other fluid maintained under carefully controlled constant pressure conditions.

In the preferred and illustrated embodiment of the invention the lathe carriage is rockably mounted on a shaft and has the cam follower and the jack mounted thereon on opposite sides of the shaft. The cam follower rides a cam that is xed to the frame of the lathe. The jack carries a follower that rides on an accurately finished flat surface also aiXed to the frame of the lathe. Oil or other jack actuating fluid is supplied to the jack by means of a pump. The pressure of the jack actuating iiuid is accurately regulated by a relief Valve arrangement. Apressure is selected for holding the follower in good riding contact with the cam and as the follower is raised 2 and lowered by the cam, the carriage is rockedI to carry the jack therewith. The jack urged fol-1. lower riding on the fiat finished surface carriedI by the lathe is held thereon in good bearing 'con' tact by the jack and the oil or other jack actuating fluid will ow to and from the jack to hold" the desired riding contact of both followers on,v their respective cam and plate surfaces. The plate for the jack carried follower can loeA used' for all types of profiles and contours. It is only, necessary to provide a single cam for each desired y profile or contour. f

It is then an object of this invention to provide.v a fluid pressure controlled adjuster for camacf' tuated devices. Y Another object of this invention is to provide a hydraulic adjuster for maintaining cam followers in constant riding engagement with operating l cams irrespective of the contour affordedy by" these cams. i y A specific object of this invention is to increase* the accuracy of profile and contour cutting lathes" ylay-eliminating play or looseness in the cam and'y follower devices of such lathes. y f A further specific object of this invention is to provide a lathe having a carriage rockedr by a cam with a fluid pressure actuator that insures( rocking of the carriage only by the cam. Another object of this invention is tol climi-"1 nate the heretofore necessary opposed cams for contour and profile turning lathes.

Other and further objects of this invention will be apparent to those skilled in the art from thel following detailed description of the amie'xed sheets of drawings which, by way of a preferred example only illustrate one embodiment of :the'f invention. v On the drawings: Figure 1 is a front side elevational view of a lathe equipped with a hydraulic cam adjuster ac-y cording to this invention.

Figure 2 is a transverse cross sectional view, with parts in end elevation, taken along the line II-II OfFig. 1. f

Figure I3 is an enlarged axial cross sectional view, with parts in elevation, of the-hydraulic jack for maintaining the cam followerrof the`r` lathe shown in Figs. 1 and 2 in constant'bearing engagement with its actuating cam. v i Figure 4 is an enlarged horizontal crossjsec-v in .transversey a'pe tional view, with parts in plan, taken along the lines IV--IV of Fig. l.

Figure is a diagrammatic'view illustrating the fluid circuit for actuating the jack of Fig. 3'.

and rear side a'filsISan'fd I4 and ai. longitudinally extending support post or rodV I 5 between the rails I3 and I4.

A lathe'carriage I6 is slidable and roekable ori the post I5 and extends transversely"adtl'lei' verseiy of the lathe siidabiy supprtiig-a-,fpit` form I1 which is adjusted by means of a screw .The i.

4 carriage I6 and acting on the accurately finished fiat top surface 32 of a plate or bar 33 carried by the rear rail I 4 of the lathe.

A sleeve-like housing 34 having a mounting pad 35 is bolted onto a rear vertical face or wall I6a of the carriage I6 as shown in Fig. 2. This housing 34, as shown in Fig. 3, has a cylindrical bore 36 therethrough. An adapter sleeve 3'! is seated in the bore 36 and has the top flange 38 overlying the top of the housing 34. The adapter sleeve 31 has a threaded end 39 extending through.. the bottom oi -the housing.V 34. An adapter rin 4mm/ threaded ontoth threaded end 39m of the sleeve 31 and is tightened against the bottom of the housing 34 to secure the sleeve 31 `tothe housing.

carriage I9 which is adjustable in a longitudinaldirection on the platform.` A tool post or` holder Ii carried bythe tool carriage I3 and projects fo liv therefrom so as; tt enter the' Y an 22'. est shown 4, aie secured i i rtur'esmthe forward endzoft'he post 2d a'd projecttherefrom to act on the work' DQ 4 `Thell'at'lie carriage I Iir has a laterally' projecting afm 23, ovrhiangig the from ran., is aria ed'uppd vvith depending ears'orlu'g's win Aspaced opposed relation at its outer end. A cam follower mounted dri the afm by' means" of a lzt' which extends through. the ears. The carri. follower; 25 has: depending rib 21 with?4 rounded iio'seflile endedge of appreciable length as shown in Figs. land.; "y n Y The rail I3 ofthe lathe yhas a cam support bar or former bar 26 bolted thereon. .This bar. 28 his a recessin itsztop central portion receiving. a cam bar 29. The cam bar is secured to the bar 28. The topedge of the cam bar 28-'has two cam grooves or depressions therein which determine the prole or `contour lto be out in the workpiece I2. Q v The cam follower 25 has its rib portion 271l arranged for .riding'onn the top edge of `the ca-mf bar 29 intouand out yof the grooves 361thereof to cause controlled rocking of the lathe carriage I 6 on posit-I5.` This rocking of the carriage Iwill swing the tool post 20 toward and away from' the inner Wall of the work piece i2 to carry'the tools 2I and 22 in a control-led swinging path as they are advanced intothe' workpiece; The type oLam grooves 30 illustrated in'l the drawings will cause the formation of an arcuate concave irinerwalxl I2@ ntlie work piece', asshown in Fig. 4. The tool 2I acts on the work piece I2 ahead of the tool 22 and its movemenlti-s controlled by the right handl caml groove 30 shown in Fig. to produce a roughcut inY the work' piece. 'I'he tool 2| passes norruoletely through the workpiece as shown in Fig. il and the following tool 22 thenvacts on the inner wail of the work piece to finish the wall surface. The right hand camgg-roove-.Bll controls'rnovementwo the .tool 2I as it is' acting on the inner :Wall of th'e- Work Pie9e|2.... Y'

cadence. with this" erection .the @am fllowr 25 is constantly heldin.goodbearing were .Winti-@etai edge' the. .Cam barzany means of a hydraulic jack 3I carried by the lathe sleeve* 31 has a partition Wall 4I intermediate its ends with a central aperture 42 there- 'tliugh The partition Wall divides the interior '.of the adapter' sleeve 31 into a lower plunger bore 43 and an upper internally threaded portion 44;;

`Ahead cap 45 has an integral depending extern-ally threaded portion 46 threaded into the portion 44 of the'sleeve ndvbottomon the partition wat' 41.

than trie aperture; 42 of the partition" wali- 41j'. Chamber` cap y45 through th'epprtion cylinder roundsltie reduced portion 56'. lPacking rings 531 separated .by washers 54 are disposed ,around the prtio' 5Il of the lation above ther ring 52. A springwasher l.35is

.seated on top of the-top washer, 54. and isf.co1n

pressedby ametalring 56 threaded on thef upper end of the portion 5I). lThe assembly of 'rings 52y and.r 56' with the packing and washers therebetween pro'vi'des; a piston head sli'dably engaging the cylinder 41 and preventing leakage of'fluid@ from theA space in thev cylinder above the-ram:A

Flu-id i'svintroduced into the topf endet thecylinder 41 through a port 51 at `the end of a'. passage Way 58 provided in the cap 45. The cap'y 45 has Aan internally threaded nipple y59 comn.

municating withthe passage 58 and receiving in threaded relation thereiny a coupling tting- 6B on the end of aflexible hose or tube 6 E. v

The bore 4-3-.of the sleevey 31 slidably receives "inl snug riding engagement therein -a cylindrical` This plunger 62 has anupwardlyrA plunger 62. projecting pin portion 63 anchored inv a holeprvidedin the bottom of' the rod 49. The plunger` 62 hasaY transversely slotted end64 receiving'in free .tiltable relation therein a cam follower 65.(`

The cam follower is pvoted ona pinl 66' extending' across the tranvers'e'ly slotte'd end 6'4 of the pl'niger. 32 of the plate or bar 33.

As shownin Fig: 5, operating fluid such as o'll for thevjack 3| is supplied from a-Itankl. AI pump. suchlas a positive displacement pump 68,- .1 pressures oil fror'n the 4tank 61 through the hose" 6I into the top of the cylindrical chamber 41..;.Ai1 5 bypass conduit 6 9 connects :the pressure side of.;-

the pump 68 back to the tank 61 and a sensitive K n This pap 45 deiin'es an"` internal cyimuriear chanter' 41; Ofighuy larger'. diameter 451.' extends from the closed top' of the. .46 t0', the' aperture 42.

This'I cam follower 65 rides on the top Wall pressure relief valve 'l0 is provided in the bypass conduit 69. Oilfprssured into the cylinder chamber 4l will force the ram 48 downwardly' to urge the cam follower B5`againstrthe top face 32 of the plate 33 andthis will cause a reaction on the lathe carriage' l5' tending to rock the carriage to move the carri` follower 25 vagainst the cam bar 29. The cam bar 29 'of course resists the rocking movement and any desired amount of pressure between the follower 25 and the cam bar 2S can be maintained by regulation of the relief valve 'l0 which controls oil pressure in the jack 3l. As the cam follower 25 is moved along the cam bar 29 into a cam groove 30, the constant pressure of oil in the jack 3l will immediately force the ram 48 in a downward direction to maintain the cam follower 65 against the surface 32 thereby rocking the tool carriage V6. Conversely, when the cam follower 25 rides out of a cam groove 3B, increased pressure in the jack cylinder 4l will be produced because the cam follower 25 will rock the carriage in a clockwise direction thereby moving the jack closer to the surface 32. In such event the relief valve immediately relieves fluid back to the tank 61 to maintain the predetermined constant pressure in the jack.

In view of the above description it will be clear that this invention provides a hydraulic cam adjuster which will hold a cam follower in constant bearing engagement with a cam under the same pressure load conditions irrespective of movements imparted to the follower by the cam.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

We claim as our invention:

l. A prole or contour forming lathe which comprises a main frame, a lathe post supported by said main frame, a lathe carriage slidable and rockable on said post, a driven lathe head on said lathe for rotatably supporting a work piece, said carriage having means for supporting a cutting tool to act on work supported by said head, a cam follower pivotally carried by said carriage, a cam secured on said main frame on one side of said post` a plate having a fiat accurately finished surface secured on said main frame on the other side of said post, a fluid pressure actuated jack on said carriage, a cam follower pivoted on the ram of said jack and acting on said plate, and means for maintaining fluid under constant pressure in said jack to rock the tool carriage and hold both cam followers in constant engagement with the cam and accurately finished surface of the plate respectively.

2. A hydraulic cam adjuster for a rockable lathe carriage having a cani follower pivotally suspended from one side thereof and a cam coacting with said follower to rock the carriage, a hydraulic jack on said carriage having a slidably mounted ram therein, a cam follower pivoted on said ram and projecting from the jack, a plate having an accurately finished flat surface receiving said cam follower thereon, a pump supplying fluid under pressure to said jack, a bypass between said pump and jack, and a pressure relief valve in said bypass adapted to maintain a constant pressure on fluid in the jack and to permit now of fluid out of the jack whenever pressures exceed a predetermined limit whereby said jack actuated caml follower will act onsaid5'sur'facef of said plateto urge the rocking of thetoolcar# riage in one direction while said cam will act' on" the opposite direction. y A A m 3. A hydraulic cam adjuster for a tool carriage the other cam follower to rock the carriage in comprising a jack housing arranged for mountiiig on a tool carriage,l said jack housing having-a' Atransversely slotted bottom end, a cam follower extending into the slotted end of said plunger, a pivot pin connecting said cam follower and plunger to pivotally support the follower on the plunger, and means for introducing actuating fiuid into said piston chamber above the piston therein.

4. The combination in a contour forming lathe of -a main frame, a lathe post supported by said main frame, a lathe carriage slidable and rockable on said post, a driven lathe head on said frame for rotatably supporting a work piece, said carriage having means for supporting a cutting tool to act on work supported by said head, first and second cam followers respectively pivoted to said carriage on opposite sides of the rocking axis thereof, a cam acting on said first follower to impart controlled rocking movement to said carriage as it slides, an abutment on said main frame receiving said second follower in riding relation thereon, and uid pressure means to `act on the second follower to urge it against said abutment with a constant force for holding said first follower in constant bearing engagement with said first cam.

5. The combination in a contour forming lathe of a main frame, a lathe post supported by said main frame, a lathe carriage slidable and rockable on said post, a driven lathe head on said frame for rotatably supporting a work piece, said carriage having means for supporting a cutting tool to act on work supported by said head, first and second cam followers respectively connected to said carriage on opposite sides of the rocking axis thereof, a cam acting on said first follower to impart controlled rocking movement to said carriage as it slides, an abutment on said main frame receiving said second follower in riding relation thereon, a hydraulic jack mounted to support said second follower from said carriage, said jack including a piston operable to urge said second follower against said abutment in accord with the fluid pressure in said jack, and means operable to maintain constant fiuid pressure in said jack to urge said second follower against said abutment with a constant force for holding said first follower in constant bearing engagement with said first cam.

6. The combination in -a contour forming lathe of a, main frame, a lathe post supported by said main frame, a lathe carriage slidable and rockable on said post, a driven lathe head on said frame for rotatably supporting a, work piece, said carriage having means for supporting a cutting tool to act on work supported by said head, first and second cam followers respectively mounted on said carriage on opposite sides of the rocking axis thereof, a cam acting on said first follower to impart controlled rocking movement to said carriage as it slides, an abutment on said main frame having a smooth contour in the direction of sliding of said carriage receiving said second follower in riding relation thereon, a hydraulic jack en .said earriage to upport said wenn@ R, Y D

mllawex, said ack including a piston operable to EFERENCES CITE y wie: Smid; eorld fQllQWer against said abutment The following references are Y.of record 1n @the in weer@ with the .fluid pressure in said jack, and me of .this patent; n means operable to maintain corllstant Yltlid. pree- 5 UNITED kSTATES PATENTS Sure. in .Sam Jack t0 urge. sald'lack agamst sam 1 hmiment with a constant forceful holding said Number .Name Date first. ollgwer in censtant bearing engagement with 211461774 SI1-adel Feb- 14. 1939 su@ first @am 2,395,365 WilSQn et al. Feb. .19. 1946 CIFLESTER c. MOORE. 1n CARL F.K1NG, JR. 

